Paranoid at night even when im not alone?

im bipolar but off my meds. but even on and before the meds i have always been paranoid at night. i constantly check the locks and sometimes hear things not voices but noises that make me creep around the house looking for something. i cant sit with my back toward a door because it makes me feel uneasy. and from this i also have a problem going to sleep even on sleeping pills i just lay there anticipating something. i usually fall asleep around 2 am and back up at 8 am.